1. Field of the Invention
The present invention relates to a control method for an image reading system in which an image obtained by scanning an original is read by an image sensor for conversion to an electric image signal, and the electric image signal is converted to a digital image signal by an A/D converter for transfer to an external device.
2. Description of the Related Art
The above-mentioned type of image reading system has recently been designed such that a user can select the kind of an original (e.g., a photo, a text document, or a film) to be read and can cut out (clip) a portion of an original image required for the reading while a preview of the original is displayed. Necessary image processing is executed in match with the required image portion and main reading of the image is performed after the user has confirmed the result of the image processing based on the displayed preview.
In order to allow the user to more easily perform the image reading, Japanese Patent Laid-Open No. 2005-311947, for example, proposes auto-mode reading in which the above-described process is executed in a fully automatic manner.
With the proposed related art, however, a fairly long time is required to automatically determine the kind of an original by the auto-mode reading in which the original is read without requiring the user to perform any more operation than just pressing a scan button. Another problem is that the determination result may be a different kind of original from the actual one in some cases.
For example, with a scanner arrangement at a current level, different lamps are turned on between when a reflective original is read and when a transmissive original is read. It is therefore required to determine whether the original to be read is a reflective original or a transmissive original.
In a currently prevailing scanner, because the determination as to whether the original to be read is a reflective original or a transmissive original is made by using data read by a CCD sensor, a light source has to be stabilized before start of the reading by the CCD sensor. More specifically, because a fluorescent lamp is used as the light source, the light source has to be stabilized at the time of turning-on thereof and about 1 minute is required to stabilize the light source. Hence, a time of 1 minute or longer is required until the kind of the original is automatically determined after power-on of the scanner. In other words, the currently prevailing scanner has a problem that the time required to automatically determine the kind of the original is fairly long.
The auto-mode is convenient in that the image processing is automatically executed after scanning and reading the original without requiring any operation by the user. However, the image processing not demanded by the user is also executed in some cases. Such a case causes a problem of requiring a longer processing time than expected by the user.
Another problem with the auto-mode is that the result of executing the image processing may provide an image differing from that desired by the user.
Still another problem with the auto-mode is that the result of automatically determining the kind of the original may differ from the actual kind of the original expected by the user.